A Clojure library to minify JavaScript code.
Use it as an extra optimisation step in your release process to make the JavaScrip file(s) smaller.
Use the Google Closure Compiler normally but when releasing files in :advanced mode, use this library to further compress the files. There can be 20% gain on the final file served.
Please note that one of the dependencies is not on maven. So please add the follwowing to you leiningen project.clj:
:repositories [["bintray.jbrotli" "http://dl.bintray.com/nitram509/jbrotli"]]If using boot, the equivalent is:
(set-env!
:repositories #(conj % '["bintray" {:url "http://dl.bintray.com/nitram509/jbrotli"}]))The minifier provides two functions called minify-css and minify-js, both functions accept a source path followed by the output target and an optional parameter map. The source can be a filename, a directory, or a sequence of directories and or filenames.
(ns my.ns
(:require [nha.boot-uglify.core :refer [minify-js]]))
;; (minify-js in out) ;; operates on files or directories
;; on a single input file
(minify-js "arrays.js" "arrays.min.js") ;;=> {:errors '(), :warnings '(), :sources '("arrays.js"), :target "arrays.min.js", :original-size 153, :compressed-size 47, :original-gzipped-size 109, :gzipped-size 55}
;; several input files
(minify-js ["file1.js" "file2.js"] "twofiles.min.js") ;; {:errors '(), :warnings '(), :sources '("arrays.js" "blocks.js"), :target "twofiles.min.js", :original-size 336, :compressed-size 121, :original-gzipped-size 197, :gzipped-size 114}
;; a directory
(minify-js "js-files-dir/" "all.min.js")
Relevant parts to add to the build.boot :
(set-env! :dependencies '[;; ...
[nha/boot-uglify "2.8.29"]
])
(require
;;...
'[nha.boot-uglify :refer [uglify]]
)
;; sample task
(deftask package
"Build the package"
[]
(comp
;;(watch)
(cljs :optimizations :advanced)
(uglify) ;; put after the cljs task
;;(aot)
;;(pom)
;;(uber)
;;(jar)
))
The default options are:
(def default-options {:sequences true, ; join consecutive statemets with the “comma operator”
:properties true, ; optimize property access: a["foo"] → a.foo
:dead_code true, ; discard unreachable code
:drop_debugger true, ; discard “debugger” statements
:unsafe false, ; some unsafe optimizations
:conditionals true, ; optimize if-s and conditional expressions
:comparisons true, ; optimize comparisons
:evaluate true, ; evaluate constant expressions
:booleans true, ; optimize boolean expressions
:loops true, ; optimize loops
:unused true, ; drop unused variables/functions
:hoist_funs true, ; hoist function declarations
:hoist_vars false, ; hoist variable declarations
:if_return true, ; optimize if-s followed by return/continue
:join_vars true, ; join var declarations
:cascade true, ; try to cascade `right` into `left` in sequences
:side_effects true, ; drop side-effect-free statements
:warnings true, ; warn about potentially dangerous optimizations/code
:global_defs {}, ; global definitions
:mangle false ; mangle names
})The following libraries were a source of inspiration or code (or both):
Remaining bugs are mine though.